Modular robot

ABSTRACT

A coverage robot including a chassis, multiple drive wheel assemblies disposed on the chassis, and a cleaning assembly carried by the chassis. Each drive wheel assembly including a drive wheel assembly housing, a wheel rotatably coupled to the housing, and a wheel drive motor carried by the drive wheel assembly housing and operable to drive the wheel. The cleaning assembly including a cleaning assembly housing, a cleaning head rotatably coupled to the cleaning assembly housing, and a cleaning drive motor carried by cleaning assembly housing and operable to drive the cleaning head. The wheel assemblies and the cleaning assembly are each separately and independently removable from respective receptacles of the chassis as complete units.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation (and claims the benefit of priorityunder 35 USC 120) of U.S. application Ser. No. 13/314,414, filed Dec. 8,2011, which is a continuation of U.S. application Ser. No. 11/633,886,filed Dec. 4, 2006, as well as claims priority under 35 U.S.C. 119(e) toa U.S. provisional patent application filed on Dec. 2, 2005, entitled“ROBOT NETWORKING, THEMING AND COMMUNICATION SYSTEM” and having assignedSer. No. 60/741,442. The disclosure of the prior applications areconsidered part of (and are incorporated by reference in) the disclosureof this application.

TECHNICAL FIELD

This invention relates to robots, and more particularly to coveragerobots.

BACKGROUND

In the field of home, office and/or consumer-oriented robotics, mobilerobots that perform household functions such as vacuum cleaning havebeen widely adopted, and examples of robots that perform floor washing,patrolling, lawn cutting and other such tasks may be found. Mobilerobots contain many components, some of which may wear out or requireservice before other components. Generally, when one component fails therobot may be greatly hindered or fail as a whole. A user may be requiredto send the whole robot to a repair service for servicing, which maythen require disassembling significant portions of the robot, or if therepair cost exceeds the value of the robot, the robot may be discarded.Alternatively, the user may need to purchase an entirely new robot.

SUMMARY

Coverage robots have a number of components that may require periodicservicing over the life of the robot. A coverage robot is used forcovering a surface. This includes cleaning as well as polishing,painting, resurfacing, sweeping, sterilizing, applying treatments, andmore. A modular coverage robot that allows the removal of discretecomponents or assemblies for repair or replacement improves theserviceability of the robot and increases the overall life of the robot.In addition, some modules can be changed for an alternative module thatfits in the same shaped cavity but has different functionality. Ingeneral, the following modules can be removed from a coverage robot andreplaced without affecting the functionality of the robot: a maincleaning head, a side brush cleaning head, a wheel module, a vacuum bin,a replaceable upper panel or cover, a remote control dockable in acover, a replaceable lower retaining panel, cover or skid, a battery, abumper, and a front wheel caster.

In one aspect, the coverage robot includes a chassis, multiple drivewheel assemblies disposed on the chassis, and a working assemblyincluding a working head (e.g., cleaning assembly) carried by thechassis. Each drive wheel assembly (e.g., drive wheel module) includes adrive wheel assembly housing, a wheel rotatably coupled to the housing,and a wheel drive motor carried by the drive wheel assembly housing andoperable to drive the wheel. The cleaning assembly (e.g., work headmodule) includes a cleaning assembly housing, a cleaning head rotatablycoupled (e.g., a work head coupled for working movement) to the cleaningassembly housing, and a cleaning drive motor carried by cleaningassembly housing and operable to drive the cleaning head. The wheelassemblies and the cleaning assembly are each separately andindependently removable from respective receptacles of the chassis ascartridges or complete units. The receptacles may be shaped cavitieshaving receiving walls which surround and guide matching outer wallshapes of a cartridge or module, such that each module slips into andfits a corresponding shaped cavity. Parallel with at least one (e.g.,insertion) direction, the walls of the module and corresponding shapedcavity may be essentially parallel, so that a module is guided to entera mating shaped cavity along a straight line. The modules may be securedin the chassis by fasteners and/or an access or retaining cover.

In one implementation, each drive wheel assembly also includes a linkagesuspending the wheel from a forward portion of the chassis. Byconnecting a first end of the linkage to a forward portion of thechassis and allowing the wheel connected to a second end of the linkageto move radially about the first end of the linkage and vertically withrespect to the chassis, the robot can traverse thresholds andtransitions easier than a robot without such a linkage. The linkage alsofacilitates an upwind tilt of the chassis in response to torque from thewheel which also aids the robot's traversal of thresholds andtransitions.

In another example, wheel assembly (modular or not modular) includes atleast part of a proximity sensor to detect an absence of an adjacentfloor. The proximity sensor may be an infrared (IR) emitter and receiverpair, where the IR emitter and receiver are located on either side ofthe wheel and positioned to emit and receive an IR beam emitted at anangle that reflects off a floor surface below the wheel. In the absenceof a floor, the emitted IR beam is not reflected off the floor and notreceived by the IR receiver. When the proximity sensor senses an absenceof the floor, a robot controller is notified so as to initiate a cliffavoidance maneuver.

In one implementation, each wheel assembly also includes a powerconnector disposed on an outer surface of the drive wheel assemblyhousing and configured to mate with a corresponding chassis powerconnector within its respective receptacle as the drive wheel assemblyis placed within the receptacle, to establish an electric powerconnection to the wheel assembly. Similarly, the cleaning assembly mayalso include a power connector disposed on an outer surface of thecleaning assembly housing and configured to mate with a correspondingchassis power connector within its respective receptacle as the cleaningassembly is placed within the receptacle, to establish an electric powerconnection to the cleaning assembly. The connectors may align with oneanother in a straight line as a module in guided to enter a matingshaped cavity along a straight line.

In some implementations, the power connector for each module is atool-less (operable without tools) module-side electrical plugs thatmates with a corresponding tool-less module-side electrical plugs on thechassis.

In one example, the cleaning robot also includes an electric battery orelectrochemical cell carried by the chassis. The electric batteryprovides power to the robot.

In another example, the cleaning robot includes a removable caster wheelassembly disposed on the chassis. The removable caster wheel assemblyprovides additional support between the robot and the floor.

In another example, the robot includes a removable cover (e.g., aretaining or access cover) secured to a bottom of the chassis. The coversecures each wheel assembly and cleaning assembly within theirrespective receptacles. The robot may also include a removable cover(e.g., an aesthetic or functional panel, e.g., as disclosed in U.S.Provisional Patent Application No. 60/741,442, herein incorporated byreference in its entirety) disposed on an upper portion of the chassis.The removable cover on the upper portion of the chassis allows an ownerto attach themed or functional covers or panels having a variety ofcolors and indicia; or, e.g., additional sensors for, e.g., navigationor obstacle detection. In one instance, the removable cover includes asegmented maintenance display panel substantially mimicking theappearance of the robot. Illuminable indicia corresponding to eachmodule receptacle is disposed on the segmented maintenance display. Themodule receptacles individually correspond to a drive wheel assembly,cleaning assembly, battery, or cleaning bin, respectively. In anotherinstance, the removable cover includes an audio output device fordelivering instructions or alerting a user of a jam or some otherproblem with the robot. The controller board on the robot controls theillumination of indicia and the audio responses from the audio outputdevice to communicate service needs or instructions to a user.

The controller may use the illuminable indicia to communicateinformation to a user. Some examples include: a steady light indicatesmodule issue; a blinking light indicates usage of a module; no blinkinglight during normal rotation of the cleaning head during cleaning;blinking light during reverse rotation of the cleaning head during asurface prep operation.

In some implementations, the robot includes a removable bumper disposedon a forward portion of the chassis. The bumper protects the robot andobjects that come in contact with the bumper.

In one example, the cleaning robot includes a cleaning bin carried bythe chassis and arranged to collect debris (including, e.g., wasteliquid) removed from a work surface by the cleaning head. The cleaningbin may include a bin housing defining a debris cavity and a filtercavity, as well as a bin filter, and a bin cover. More than one debriscavity may be provided, e.g., a swept debris cavity and a vacuumeddebris cavity. If a cleaning treatment or fluid is applied, a cleaningbin may include a clean fluid dispensing portion. The debris cavity isconfigured to collect debris removed from a work surface by the cleaninghead. The filter cavity is configured to collect debris removed from awork surface by a vacuum fan in fluid communication with the filtercavity. The bin filter is disposed in the filter cavity and isconfigured to substantially inhibit particulate from entering the vacuumfan. The bin cover is rotatably attached to the bin housing andconfigured to move between a bin closed position and a bin openposition, exposing the filter cavity and the bin filter for servicing.

In one implementation, the cleaning bin also includes a bin cover springactuator that biases the bin cover in the open position. When thecleaning bin is installed on the robot, the bin cover is held closed.When the cleaning bin is removed from the robot, the bin cover isactuated open by the spring exposing the filter cavity and the binfilter for servicing. The cleaning bin may also include a latch to holdthe biased bin cover in the closed position, allowing a user toselectively open the bin cover.

In another implementation, the cleaning bin also includes for a modularionic charged, washable, removable filter-plate in the filter cavity.

In one example, the cleaning head rotation includes brushes and thedirection of rotation is reversed allowing the cleaning assembly to actas a surface (carpet) prep device. In this example, the bin carries aliquid or a powder (fresheners, etc) that is dispensed by the cleaninghead onto the floor surface.

The details of one or more implementations of the disclosure are setforth in the accompanying drawings and the description below. Otherfeatures, objects, and advantages of the disclosure will be apparentfrom the description and drawings, and from the claims.

DESCRIPTION OF DRAWINGS

FIG. 1A is a top perspective view showing an example of a coveragerobot.

FIG. 1B is a bottom perspective view showing an example of a coveragerobot.

FIG. 1C is a sectional view showing an example of a coverage robot.

FIG. 1D is a sectional view showing an example of a coverage robot.

FIG. 1E is a cross-sectional view showing shaped cavities, matingmodules, and parallel outer walls of a coverage robot.

FIG. 1F is a cross-sectional view showing shaped cavities, matingmodules, and parallel outer walls of a coverage robot.

FIGS. 2A and 2B are exploded views showing examples of a chassis, afunctional core cover, a top panel, and a retaining cover of a coveragerobot.

FIG. 3 is an exploded view showing an example of cleaning assemblies,drive wheel assemblies, a battery, and a bottom cover of a coveragerobot.

FIG. 4A is a perspective view showing an example of a horizontalcleaning head.

FIG. 4B is a perspective view showing an example of a vertical cleaningassembly.

FIG. 4C is a schematic view showing an example of a vertical cleaningassembly.

FIG. 5 is a perspective view showing an example of a coverage robotbumper.

FIG. 6 is an exploded view showing an example of a cleaning bin.

FIGS. 7A-B are cross-sectional views showing examples of cleaning binsincluding cleaning bin covers.

FIG. 8 is an exploded view showing an example of a caster wheelassembly.

FIG. 9A is an exploded view showing an example of a wheel-drop sensor.

FIG. 9B is a cross-sectional view showing an example of a caster wheelassembly.

FIG. 10A is an exploded view from a top perspective showing an exampleof a drive wheel assembly.

FIG. 10B is a front view of a power connector.

FIG. 11 is an exploded view from a bottom perspective showing an exampleof a drive wheel assembly.

FIG. 12 is a perspective view showing an example of a cleaning assembly.

FIG. 13 is a bottom perspective view showing an example of a cleaninghead assembly.

FIG. 14 is a top perspective view showing an example of a cleaning headassembly.

FIG. 15 is a schematic view showing an example of a coverage robot.

FIG. 16 is a schematic view showing an example of a coverage robotservicing process.

FIG. 17 is a top perspective view showing an example of a coveragerobot. Like reference symbols in the various drawings indicate likeelements.

DETAILED DESCRIPTION

FIG. 1A is a top perspective view showing an example of a coverage robot100. The coverage robot 100 may be used to clean a work surface, such asa floor or wall by vacuuming debris brushed from the work surface.Coverage robot 100 includes modular components that are separately andindependently removable from the coverage robot 100. A coverage robot isused for covering a surface. This includes cleaning as well aspolishing, painting, resurfacing, sweeping, sterilizing, applyingtreatments, and more.

The top view of the coverage robot 100 shows a removable cleaningassembly 102, a removable top cover 104, a removable decorative cover106, and a removable bumper 108. In one implementation, the cleaningassembly 102 moves debris on the work surface to a suction path underthe coverage robot 100. The top cover 104 covers internal components onthe top side of the coverage robot 100. The decorative cover 106 is usedto change the appearance or style of the coverage robot 100, such aswith colors or themes. The decorative cover 106 may also oralternatively be a functional panel or plate that carries sensors,interfaces, actuators, and the like (e.g., the cover 106 may be providedwith some or all of its own microprocessor, mounted sensors, mountedactuators, and/or a plug interface to the robot itself). Differentdecorative covers 106 or different functional covers (not shown) may beinterchangeably mounted as modules if they have the same outer shape,e.g., outer wall configuration matching a shaped cover-receiving cavityor recess in the robot 100. The bumper 108 protects the coverage robot100 and objects the coverage robot 100 comes in contact with during thecontact.

Modular components, such as the cleaning assembly 102, the top cover104, the decorative cover 106, and the bumper 108, are arranged to bemountable into mating shaped receiving cavities and may be separatelyand independently removed from the coverage robot 100. For example, abroken or worn component may be removed and replaced with a properlyfunctioning component or a malfunctioning component may be fixed andused again. In an alternative example, a component, such as thedecorative cover 106, may be replaced to change the style or appearanceof the coverage robot 100. In another example, a component may bereplaced to change the function of the coverage robot 100, such as byreplacing stiff brushes in the cleaning assembly 102 with soft brushes.

FIG. 1B is a bottom perspective view showing an example of the coveragerobot 100. The bottom view of the coverage robot 100 shows removabledrive wheel assemblies 110 a-b, a second removable cleaning assembly112, a removable caster wheel assembly 114, a removable cleaning bin116, and a removable bottom cover 118. The drive wheel assemblies 110a-b provide propulsion for the coverage robot 100. The second cleaningassembly 112 also moves debris on the work surface toward a suction pathunder the coverage robot 100. The caster wheel assembly 114 provides athird point of contact with the work surface. The cleaning bin 116stores debris that the coverage robot 100 vacuums from the work surface.The bottom cover 118 helps secure shaped modules, such as the cleaningassemblies 102 and 112, the drive wheel assemblies 110 a-b, and thecaster wheel assembly 114 in the coverage robot 100.

Referring to FIGS. 1C and 1D, shaped modules (e.g., modules 110, 112,110 b, 102 shown in schematic form) may be provided with mechanicalconnectors (e.g., for accepting a fastener, or that is itself afastener) 1003 a, 1403, 411 as well as electrical connectors 1002 a,1402, 410. The mechanical connectors on the shaped modules align withcorresponding connectors, fixtures or hardpoints 205, 209, 211 formed inthe robot chassis 202, and the electrical connectors on the shapedmodules simultaneously align with mating connectors 204, 208, 206, 210formed in the robot chassis 202, when a shaped module is e.g., slid intoits mating shaped receiving cavity. This allows the modules to besecurely mounted, and the power connectors to provide power to eachmodule.

Referring to FIGS. 1E and 1F, the chassis 202 is formed as a unibodystructure, including downward-facing shaped receptacle cavities. In FIG.1E, shaped receptacle 304, which matches the wheel module 110 a housing,shaped receptacle 306/310, which matches the wheel module 110 b housingand side brush module 340 housing and working head shaped receptacle308, which matches the working head module housing 332, are shown. Eachshaped receptacle is an irregular cup, having a plug in or on the bottomwall of the cup, a perimeter of parallel walls in the shape of themodules to be accepted, and an open side facing the bottom cover 110. Asan example, parallel walls 304 a and bottom wall 304 b are illustratedin FIGS. 1E and 1F, although each of the shaped receptacles may havesimilar features. As illustrated in schematic form, the bottom of therobot 100 includes several modules. The parallel walls of the shapedreceptacles and the matching parallel walls of the matching modules area tight slip fit (if the module is to form part of the structuralmonocoque of the body) and a loose slip fit (if the module is to bequiet but will not significantly contribute to the rigidity of themobile robot). As parallel walls, they permit the module to be directlyslipped into the receiving shaped receptacle “cup” along the walls tothe bottom (where, as discussed herein, an electrical connector to plugin the same straight direction is received by a plug at the bottom orside of the receptacle). As shown in FIGS. 1E and. 1F, two neighboringshaped receptacles may share a wall (e.g., as the working headreceptacle 308 shares walls with the wheel module receptacles 304, 306);and a single receptacle may receive more than one module, so long asthose modules also have parallel walls where they abut one another(e.g., as the wheel module receptacle 306 and side brush modulereceptacle 310 are interconnected, and the wheel module wall or housing324 a and brush module housing 340 have an abutting parallel wall wherethe receptacles interconnect (or, e.g., form a single receptacle). Asillustrated in schematic form in FIG. 1E, the modules are slid intoplace in the “vertical” (e.g., parallel wall) direction until they reachthe bottom of their matching receptacle. As further illustrated, themodules may each be secured in their corresponding receptacle(s) byfasteners F, which are fastened in the same direction as the directionof insertion, permitting direct access when the cover 110 is removed. Asnoted herein, the cover 110 is preferably tool-less, having snaps,catches, sliders, or the like to secure it to the chassis, and when thecover 110 is removed, most of the modules are visible and any fastenersmay be removed to permit the module to be slid out.

FIGS. 2A-B provide exploded views showing an example of a chassis 202, afunctional shell 104, and the covers 106, and 118 of the coverage robot100. The chassis 202 carries the cleaning assemblies 102 and 112, thedrive wheel assemblies 110 a-b, and the caster wheel assembly 114 aswell as other components of the coverage robot 100. The chassis 202includes receptacles where the components are secured by the bottomcover 118. In one implementation, the chassis 202 is a unibodyconstruction that defines each receptacle for each module and includespoints of contact for parts. In this regard, as noted, the chassis 202may be formed by wholly or partially unibody or monocoque techniques, inwhich structural load is supported using the chassis's external skin(“structural skin”). The chassis 202 and top functional shell 104 mayenclose electronics such as controller board 1050 to be hermeticallysealed or waterproofed and may be rigidly secured together to form atwo-part monocoque structural support. Modules as discussed herein maybe supported by the structural skin, but may also be formed as membersof the monocoque, and/or may have an outer monocoque themselvespermitting a module slid into its shaped receiving cavity and secured tocontribute to the structural rigidity of the robot. On the other hand,the covers 106 and 118 would not generally contribute significantly tothe structural rigidity of the robot (although each could be modified todo so). FIG. 3 is an exploded view showing an example of the cleaningassemblies 102 and 112, the drive wheel assemblies 110 a-b, an electricbattery 302, and the bottom cover 118 of the coverage robot 100. Thebottom cover 118 retains the battery 302, acts as a barrier to preventinfiltration of foreign matter into the robot 100, and provides aninsulating barrier for hot surfaces. Referring to FIG. 1C-F and FIG. 3,the chassis 202 defines shaped receiving receptacles 304, 306, 308, 310,and 312 where the drive wheel assembly 110 a, the drive wheel assembly110 b, the cleaning assembly 112, the cleaning assembly 102, and theelectric battery 302 are received (by sliding parallel walls of themodule into the parallel walls of the mating shaped receivingreceptacle) and secured by the bottom cover 118, respectively. Thebottom cover 118 includes openings 314, 316, 318, 320, and 322 that aree.g., smaller than downward-facing openings of corresponding shapedreceiving receptacles to allow the drive wheel assembly 110 a, the drivewheel assembly 110 b, the cleaning assembly 112, the cleaning assembly102, and the caster wheel assembly 102, respectively, to act through thebottom cover, and in some cases, to come in contact with the worksurface.

The modularity of the bottom cover 118 allows the robot 100 to bealtered to accommodate different floor surfaces. The bottom cover 118may be disposed on the chassis 202 at various cover heights with respectto a floor to accommodate different floor types. For high pile shagcarpets, the bottom cover 118 may be coated with Teflon and the coverheight reduced, to allow the robot 100 to skim (float) on the deepcarpet with ease. Where the floor surface is primarily hard flooring, areplaceable bottom covers 118 with mustache brushes disposed on aforward portion of the bottom cover 118 may be used to channel fine dirttowards the cleaning assembly 112. Additional mustache brushes disposedon a rearward portion of the bottom cover 118 may be used to minimizeair born dust from escaping the cleaning assembly 112. When using therobot 100 to clean surfaces with many drop-offs (ledges/stairs), thebottom cover 118 may be fitted with skid pads that act as a brakingsystem to prevent the robot 100 from falling or sliding off the ledges.In another implementation, a UV light module that works in closeproximity to the floor to sanitize floors is disposed below the bottomcover 118, which is fitted with electric terminals to contact the powercontacts of one of the cleaning assemblies 102 or 112. In yet anotherimplementation, the bottom cover 118 is fitted with sand-paper flaps forprepping a factory/lab floor in need of abrasive floor cleaning before apaint layer can be applied.

The drive wheel assembly module 110 a-b includes drive wheel assemblyhousings 324 a-b, wheels 326 a-b, wheel drive motors 328 a-b, andlinkages 330 a-b, respectively. The wheels 326 a-b are rotatably coupledto the drive wheel assembly housings 324 a-b. In addition, the drivewheel assembly housings 324 a-b carry the wheel drive motors 328 a-b,respectively. The wheel drive motors 328 a-b are operable to drive thewheels 326 a-b, respectively. The linkages 330 a-b attach the drivewheel assemblies 110 a-b, respectively, to the chassis 202 at a locationforward of the wheels 326 a-b, respectively. The linkages 330 a-bsuspend the wheels 326 a-b, respectively, from the chassis 202. Thelinkages 330 a-b rotate at the connection to the chassis 202 to allowthe wheels 326 a-b, respectively, to move up and down.

The main cleaning assembly module 112 includes a cleaning assemblyhousing 332, a main brush 334, a secondary brush, and a cleaning drivemotor 336. The main brush 334, the secondary brush, a pivoting frame, awire cover or bail, and other elements moving together with the brushesto accommodate surface variations form a main cleaning head. The mainbrush 334 is rotatably coupled to the cleaning assembly housing 332 androtates to brush and clean the work surface. The cleaning assemblyhousing 332 carries a cleaning drive motor 336. The cleaning drive motor336 drives the main brush 334 and optionally a secondary brush. Thismain cleaning assembly module 112, as depicted, includes the main workhead of the robot 100 (i.e., that works and covers an area as the robotmoves forward), and the main work head the main work width of the robot100.

The lateral or side cleaning assembly module or head 102 includes acleaning assembly housing 338, a side brush 340, and a cleaning drivemotor 342. The side brush 340 is rotatably coupled to the cleaningassembly housing 338 and rotates to brush and clean the work surface,the side brush 340 extending beyond the perimeter of the robot tocollect debris along walls and in corners and direct debris in front ofthe main brush 334, to be collected by the main brush. The cleaningassembly housing 338 carries the cleaning drive motor 342. The cleaningdrive motor 342 drives the side brush 340.

The electric battery 302 provides power to components, such as the drivewheel assemblies 110 a-b and the cleaning assemblies 102 and 112, viamotor controllers and amplifiers. The drive wheel modules 110 a-b andthe cleaning modules 102 and 112 include power connectors that connectmotor power and/or control to the wheel drive motors 328 a-b and thecleaning drive motors 336 and 342, respectively. The power connectorsare located on an outer surface of the drive wheel assembly housings 324a-b and the cleaning assembly housings 332 and 338. The power connectorsmate with power connectors within the receptacles 304, 306, 308, 310,and 312 in the chassis 202.

FIG. 4A is a perspective view showing an example of a main brush 334.The main brush 334 is separately and independently removable from thecleaning head within the cleaning assembly 112 and thereby from thecoverage robot 100. The main brush 334, in this case, rotates about ahorizontal axis parallel to the work surface, and is thereby ahorizontal cleaning assembly although the main work width of a coveragerobot may include vertically rotating brushes, no brushes in lieu of avacuum, a reciprocating brush, a circulating belt member, and otherknown cleaning implements. The main brush 334 has a cylindrical body 402that defines a longitudinal axis of rotation. Bristles 404 are attachedradially to the cylindrical body 402. Flexible flaps 406 are attachedlongitudinally along the cylindrical body 402. As they rotate, thebristles 404 and the flexible flaps 406 move debris on the work surface,directing it toward a sweeper bin in the robot. In some cases, the mainbrush may also direct debris or dirt a suction path under the cleaningrobot 100. In the case of a wet cleaning robot, the main brush may haveinstead a scrubbing function, and a vacuum or other collector maycollect waste fluid after scrubbing.

FIG. 4B is a perspective view showing an example of the side cleaningassembly 102, which may be a vertical cleaning assembly. In certainimplementations, the cleaning head 340 is separately and independentlyremovable from the cleaning assembly 102 and the cleaning robot 100. Theside cleaning brush 340 rotates about a vertical axis normal to the worksurface. The cleaning brush 340 has brush elements 408 with a first endthat attaches to the cleaning head 340 at the axis of rotation and asecond end that radiates from the axis of rotation. In certainimplementations, adjacent brush elements are evenly spaced about theaxis of the cleaning head 340, such as a space of 120 degrees betweenthree elements or 60 degrees between six elements. The brush elements408 extend beyond a peripheral edge of the coverage robot 100 to movedebris adjacent to the coverage robot 100 toward the suction path underthe coverage robot 100. In some implementations, although the verticalcleaning assembly 102 is generally vertical, the cleaning head 340operates about an axis offset (tilted) from a vertical axis of thevertical cleaning assembly 102. As shown in schematic form in FIG. 4C,the brush 340 may be tilted, in both forward and side to side directions(i.e., tilted downward with respect to the plane of wheel contact abouta line about 45 degrees from the direction of travel within that plane),in order to collect debris from outside the robot's periphery toward themain work width, but not disturb such collected debris once it is thereor otherwise eject debris from the work width of the robot. The axisoffset is optionally adjustable to customize the tilt of the cleaninghead 340 to suit various carpet types, such as shag.

Referring to FIGS. 4B and 1D, the side cleaning module 102 includes apower connector 410. When the cleaning assembly 102 is placed in theshaped receptacle 310 the power connector 410 mates with a powerconnector 210 in the receptacle 310 (as described, optionally havingshaped parallel walls to guide the power connectors to mate). The matedpower connector 410 provides power to the cleaning drive motor 342 fromthe electric battery 302. A mechanical hard point or fastener 411 on theside cleaning module 102 mates with a corresponding mechanical hardpoint 211 in the receptacle 310.

FIG. 5 is a perspective view showing an example of the coverage robotbumper 108. The bumper 108 is attached to the coverage robot 100 at aforward portion of the chassis 202. The bumper 108 is separately andindependently removable from the chassis 202 and the coverage robot 100.The bumper 108 protects the coverage robot 100 and one or more objectsin the path of the coverage robot 100 during a collision with the one ormore objects.

FIG. 6 is an exploded view showing an example of the cleaning bin 116.The cleaning bin 116 includes a bottom housing 602, a middle housing604, a top housing 606, a debris cavity 607, a filter cavity 608, afilter cavity cover 609, a debris squeegee 610, and a vacuum fan 612.Referring to FIG. 2, chassis 202 defines a bin receiving slot 316 wherethe cleaning bin 116 is housed.

Together, the top housing 606 and the middle housing 604 form a debriscavity 607. The debris cavity 607 has at least one opening at itsforward side adjacent to the cleaning assembly 112. Through theopening(s), the debris cavity 607 may collect debris from the cleaningassembly 112.

Together, the bottom housing 602 and the middle housing 604 may alsoform a filter cavity 608 that stores debris vacuumed from the worksurface. The debris squeegee 610 scrubs the work surface and directsdebris into the debris cavity 608. The vacuum fan 612 is attached to thetop side of the middle housing 604. The vacuum fan 612 creates a suctionpath from the work surface at the debris squeegee 610 and through thefilter cavity 608. A filter below the vacuum fan 612 prevents debrisfrom exiting the filter cavity 608 and entering the vacuum fan 612. Thefilter cavity cover 609 is rotatably attached to the middle housing 604and is configured to move between a closed position and an openposition, which exposes the filter cavity 608 and a filter forservicing.

The cleaning bin 116 may also include a filter cavity cover springactuator 611 that biases the filter cavity cover 609 in the openposition. When the cleaning bin 116 is secured to the chassis 202 thefilter cavity cover 609 is held in a closed position. When the filtercavity cover 609 is removed from the chassis 202, the filter cavitycover spring 611 rotates the filter cavity cover 609 open, exposing thefilter cavity 608 for removal of debris. In one example, the cleaningbin 116 may also include a latch to hold the biased filter cavity cover609 in the closed position, until a user releases the latch, therebyallowing the filter cavity cover spring 611 to rotate the cover open.

The vacuum fan 612 includes a power connector 614. The power connector614 provides power to the vacuum fan 612 from the electric battery 302.The power connector 614 protrudes through an opening 616 in the tophousing 606. This allows the power connector 614 to mate with a powerconnector in the chassis 202 when the cleaning bin 116 is placed in areceptacle within the chassis 202.

FIGS. 7A-B are cross-sectional views showing examples of the cleaningbin 116 including cleaning bin covers. FIG. 7A shows an example of thecleaning bin 116 having a cleaning bin cover 702 hinged at the binhousing 606. The bin cover 702 enclose a robot side of the filter bin116. The bin cover 702 may be opened to empty the cleaning bin 116, andin particular, the debris the filter cavity 608. A bin filter 704 belowthe vacuum fan 612 retains debris vacuumed into the filter cavity 608along the suction path. The bin covers 702 may have attached springs 706or another device that bias the bin covers 702 in an open position.

In certain implementations, the bin covers 702 open as the cleaning bin116 is removed from the coverage robot 100 (as shown in FIGS. 7A, 7B).

Alternatively, the bin cover 702 may open when a bin cover latch isreleased. The latch retains the bin cover 702 in a closed position, suchas during operation of the coverage robot 100. The latch may be releasedto open the bin cover 702 and empty the cleaning bin 116. FIG. 8 is anexploded view showing an example of the caster wheel assembly 114.

The caster wheel assembly 114 is separately and independently removablefrom the chassis 202 and the coverage robot 100. The caster wheelassembly 114 includes a caster wheel housing 802, a caster wheel 804, awheel-drop sensor 806, and a wheel-floor proximity sensor 808. Thecaster wheel housing 804 carries the caster wheel 802, the wheel dropsensor 806, and wheel-floor proximity sensor 808. The caster wheel 804turns about a vertical axis and rolls about a horizontal axis in thecaster wheel housing 802.

The wheel drop sensor 806 detects downward displacement of the casterwheel 804 with respect to the chassis 202. The wheel drop sensor 806determines if the caster wheel 804 is in contact with the work surface.

The wheel-floor proximity sensor 808 is housed adjacent to the casterwheel 804. The wheel-floor proximity sensor 808 detects the proximity ofthe floor relative to the chassis 202. The wheel-floor proximity sensor808 includes an infrared (IR) emitter and an IR receiver. The IR emitterproduces an IR signal. The IR signal reflects off of the work surface.The IR receiver detects the reflected IR signal and determines theproximity of the work surface. Alternatively, the wheel-floor proximitysensor 808 may use another type of sensor, such as a visible lightsensor. The wheel-floor proximity sensor 808 prevents the coverage robot100 from moving down a cliff in the work surface, such as a stair stepor a ledge. In certain implementations, the drive wheel assemblies 110a-b each include a wheel-floor proximity sensor.

FIG. 9A is an exploded view showing an example of the wheel-drop sensor806. The wheel drop sensor 806 includes an IR emitter 902 and an IRreceiver 904. The IR emitter 902 produces an IR signal. The IR signalreflects from the caster wheel 804. The IR receiver 904 detects thereflected IR signal and determines the vertical position of the casterwheel 804.

FIG. 9B is a cross-sectional view showing an example of the caster wheelassembly 114. The view shows a top surface 906 of the caster wheel 804from which the IR signal reflects. The IR receiver 904 uses thereflected IR signal to determine the vertical position of the casterwheel 804.

FIG. 10A is an exploded view from a top perspective showing an exampleof the drive wheel assembly 110 a. The view shows the drive wheelassembly housing 324 a, the wheel drive motor 328 a, the linkage 330 a,the wheel 326 a, and the power connector 1002. FIG. 11 is an explodedview from a bottom perspective showing an example of the drive wheelassembly 110 b. The view shows the drive wheel assembly housing 324 b,the wheel drive motor 328 b, the linkage 330 b, the wheel 326 b and thepower connector 1002 b.

Referring to FIGS. 10A-B, 11, and 1C, the drive wheel assembly 110 aalso includes a power connector 1002. When the drive wheel assembly 110a is placed in the receptacle 304, the power connector 1002 a mates witha power connector 204 in the receptacle 304. This allows the powerconnector 1002 a to provide power to the wheel drive motor 328 a fromthe electric battery 302. A mechanical hard point 1003 a on the drivewheel assembly 110 a mates with a corresponding mechanical hard point205 in the receptacle 304. The power connector 1002 a on the drive wheelassembly 110 a is a floating connector (edge card) mounted to the modulehousing 324 a with pins/screws 1004 with a clearance between the pins1004, power connector 1002 a, and the walls of the module housing 324 a.The limited free-float design allows the power connector 1002 a to movea small amount when the locating features, such as the mechanical hardpoint 1003 a, in the module are engaged, thereby minimizing stress onthe connector-set during assembly and in operation.

FIG. 12 is a perspective view showing an example of the cleaning module112 (or coverage or work module, for implementations that do not“clean”. Within the cleaning module 112, the cleaning module housing 332carries a cleaning head assembly 1202. The cleaning head assembly 1202may be movable with respect to the cleaning assembly housing 332 and thecoverage robot 100. The cleaning head assembly 1202 carries the maincleaning brush 334 and the cleaning drive motor 336 (as can be seen,although a multiplicity of bristle groups are provided on the brush 334,only a few are depicted for clarity).

FIG. 13 is a bottom perspective view showing an example of the cleaninghead assembly 1202. The cleaning head assembly 1202 includes a cleaninghead assembly housing 1302. The cleaning head assembly housing 1302carries the main cleaning brush 334 and a secondary cleaning brush 1304.

The main cleaning brush 1304 is rotatably coupled to the cleaning headassembly housing 1302. The secondary cleaning brush 1304 includesflexible flaps. The secondary brush 1304 rotates in the oppositedirection to the main brush 1302, so that debris impelled by the mainbrush 1304 is caught and directed up and over the secondary brush. Inaddition, the flexible flaps may brush the work surface clean as thecleaning head 1304 rotates.

FIG. 14 is a top perspective view showing an example of the cleaninghead assembly 1202. The view shows the location of the cleaning drivemotor 336 at the back of the cleaning head assembly housing 1302.Referring to FIGS. 14 and 1C, the cleaning head assembly housing 1302also includes a power connector 1402. The power connector 1402 providespower to the cleaning drive motor 336 from the electric battery 302. Thepower connector 1402 protrudes through an opening in the cleaningassembly housing 332 when the cleaning head assembly 1202 is placed inthe cleaning assembly 112. Similar to the wheel module, the powerconnector 1402 on the drive wheel assembly 110 a is a floating connector(edge card) mounted to the module housing with pins, having a clearancebetween the pins and a C-shaped receiving slot in the edge card, as wellas surrounding the power connector 1402. When the cleaning assembly 112is placed in the receptacle 308, the power connector 1402 mates with apower connector 208 in the chassis 202 to provide power to the cleaningdrive motor 336. Mechanical hard points 1403 on the cleaning assembly112 mate with corresponding mechanical hard points 209 in the receptacle308.

In one implementation, referring to FIGS. 1C-D, the power connectors1002, 1102, 1402, and 410 are tool-less (operable without tools)module-side electrical plugs that mate with corresponding tool-lessmodule-side electrical plugs 204, 206, 208, and 210 on the chassis 202.The power connectors 1002, 1102, 1402, 410 204, 206, 208, and 210establish an electrical connection between each module (he drive wheelassembly 110 a, the drive wheel assembly 110 b, the cleaning assembly112, the cleaning assembly 102, the electric battery 302, and thecleaning bin 116) and a corresponding receptacle 304, 306, 308, 310,312, and 316, respectively, upon insertion of the module into thereceptacle.

Referring to FIGS. 1C-D, chassis 202 defines receptacle 250 in whichcontroller board 1050 is removably mounted. Power connectors 204, 206,208, and 210 in receptacles 304, 306, 308, and 310 respectively, areelectricity connected to the controller board 1050. A display panel 105is disposed above the chassis 202. The display panel 105 is inelectrical communication with the controller board 1050.

FIG. 15 is a schematic view showing an example of a robot 100 includinga display panel 105 having indicia 150 and an audio output device 160.The indicia 150 comprises a segmented maintenance display substantiallymimicking the appearance of the robot with illuminable indicia 3040,3060, 3080, 3100, 3120, and 3160 corresponding to each module receptacle304, 306, 308, 310, 312, and 316, respectively. Module receptacles 304,306, 308, 310, 312, and 316 correspond to the drive wheel assembly 110a, the drive wheel assembly 110 b, the cleaning assembly 112, thecleaning assembly 102, the electric battery 302, and the cleaning bin116, respectively. The controller board 1050 controls the illuminationof indicia 3040, 3060, 3080, 3100, 3120, and 3160 and the audioresponses from the audio output device 160 of the display panel 105 tocommunicate service needs to a user. In one example, the controllerilluminates one or more of the indicia 304, 306, 308, 310, 312, and 316on the segmented maintenance display panel 105 to indicate that a modulein one of the receptacles 304, 306, 308, 310, 312, and 316 needs to beremoved and replaced by a user.

The controller board 1050 monitors the currents delivered to the drivewheel assemblies 110 a-b and the cleaning head assemblies 102 and 112.Upon detecting an over-current, the appropriate indicia 3040, 3060,3080, and 3100 of the maintenance display 150 is illuminated by thecontroller board 1050 to indicate a jam or other obstruction to becleared. In another example, the controller board 1050 sends an audioresponse which is delivered by the audio output device 160 to provideinstructions on how to correct a problem. Once the jam or problem iscleared, a warning/maintenance display will remain illuminated if theover-current remains, indicating that replacement of the module isrequired. In one implementation, the cleaning bin 116 includes a binfull sensor that communicates a current bin capacity to the controllerboard 1050. When the controller board 1050 detects that the bin is fullit illuminates indicia 3160 to signal to a user to empty the cleaningbin 116. When the controller board 1050 detects that the battery 302 islow or in need of service it illuminates indicia 3120 to signal to auser to maintenance the battery 302. In each example, the controllerboard 1050 may have guided audio instructions delivered by the audiooutput device 160. (E.g., remove the cover, remove the module, send itin or discard it, and order a new one.) Different colors (e.g.,multi-colored LEDs or different LEDs) may be provided for each segment,in order to communicate different messages—e.g., green for no attentionneeded, yellow for jam, red for service or maintenance replacement,flashing green for ordinary care such as bin emptying, cleaning fluidreplacement, or battery charging).

Referring to FIG. 16, modularity is used to extend robot life. In oneimplementation, a user responds to illumination of the illuminableindicia 3040, 3060, 3080, 3100, 3120, and 3160 on the maintenancedisplay 105 corresponding to one or more modules or to instructionsprovided from the audio output device 160 to identify a module to bereplaced. The user communicates a maintenance request through a computer4002 over an internet 4004 to a web server 4006 which routes themaintenance request to a fulfillment center 4008. The fulfillment center4008 sends a replacement part parcel 4010 to the user. The robot 100 canprovide audio instructions on how to install the part. In anotherimplementation, the robot 100 communicates wirelessly to a local network4002, which communicates the maintenance request.

Referring to FIG. 17, the modularity of the robot 100 can be furtherextended by a module slot 190 defined in an upper portion of the robot100. The modular slot 190 is configured to accept a data module 192. Thedata module 192 is self-contained and can transport data on constituentRAM, ROM, Flash, or EEPROM type storage devices (which might be loadedwith software, video, or audio content either at a user's computerequipped with a special writing unit or at the manufacturer in order toprovide content such as themed content, for example).

In one example, the data module 192 is a recording device installable inthe module slot 190 for recording a mileage of the robot 100 and itsconstituent parts. For example, the data module 192 can record adistance driven, how often the robot 100 has been used, the life ofcertain modules, when modules have been changed, etc. Furthermore, therobot can be configured to not function without the data module 192installed. In yet another example, the data module 192 is used to changesoftware behaviors of the robot 100. The cover 106 may form the body ofthe data module 192, e.g., with additional sensors (e.g., sonar pointingforward, IR emitters/receivers in multiple directions, IR receiverspointing toward compass point directions, IR projectors pointing at theceiling, IR receivers pointing at the ceiling, gyroscope(s) arranged todetect and/or yaw), actuators (e.g., pan/tilt unit, spray unit),communication (RF or IR line of sight) or microprocessors.

“ROBOT OBSTACLE DETECTION SYSTEM”, U.S. Pat. No. 6,594,844, disclosingproximity sensors such as cliff sensors and wall following sensors;“AUTONOMOUS FLOOR-CLEANING ROBOT”, U.S. Pat. No. 6,883,201, disclosing ageneral structure of an iRobot Roomba coverage/cleaning robot and mainand edge cleaning heads in detail; “METHOD AND SYSTEM FOR MULTI-MODECOVERAGE FOR AN AUTONOMOUS ROBOT”, U.S. Pat. No. 6,809,490, disclosingmotion control and coverage behaviors, including escape behaviors,selected by an arbiter according to the principles of behavior basedrobotics; and “METHOD AND SYSTEM FOR ROBOT LOCALIZATION ANDCONFINEMENT”, U.S. Pat. No. 6,781,338, disclosing virtual walls, i.e.,robot confinement using wall-simulating directed beams, are eachincorporated by reference herein in their entireties.

Other robot details and features combinable with those described hereinmay be found in the following U.S. patent applications filedconcurrently herewith, entitled “AUTONOMOUS COVERAGE ROBOT NAVIGATIONSYSTEM” having assigned Ser. No. ______; “COVERAGE ROBOT MOBILITY”having assigned Ser. No. ______; and “ROBOT SYSTEM” having assigned Ser.No. ______, the entire contents of the aforementioned applications arehereby incorporated by reference.

A number of implementations have been described. Nevertheless, it willbe understood that various modifications may be made without departingfrom the spirit and scope of the following claims. For example, thecoverage robot may include a different number of drive wheel assembliesor cleaning assemblies than those described above. Accordingly, otherimplementations are within the scope of the following claims.

1. (canceled)
 2. A method comprising: monitoring an operational statusof a number of components of a mobile cleaning robot, the componentscomprising a drive wheel assembly and a cleaning assembly; determiningthat the operational status of a particular component does not satisfy acondition; and providing a notification indicative of the operationalstatus of the particular component based on the determining.
 3. Themethod of claim 2, comprising determining a change in the operationalstatus of the particular component.
 4. The method of claim 3, whereindetermining a change in the operational status of the particularcomponent comprises determining that the operational status of theparticular component satisfies the condition.
 5. The method of claim 3,comprising providing an updated notification responsive to the change inthe operational status of the particular component.
 6. The method ofclaim 2, wherein the notification is indicative of an instruction to (i)remove an obstruction of the particular component, (ii) replace theparticular component, or (iii) perform maintenance on the particularcomponent.
 7. The method of claim 2, wherein determining that theoperational status of the particular component does not satisfy thecondition comprises determining that an electrical current delivered tothe particular component is above a threshold.
 8. The method of claim 2,wherein determining that the operational status of the particularcomponent does not satisfy the condition comprises determining that theparticular component is obstructed or needs replacement.
 9. The methodof claim 2, wherein providing the notification comprises providing thenotification on a display of the mobile cleaning robot.
 10. The methodof claim 9, wherein providing the notification on the display comprisesproviding an image on the display representing the particular componentof the mobile cleaning robot.
 11. The method of claim 9, whereinproviding the notification on the display comprises providing aninstruction on the display to clear an obstruction of the particularcomponent.
 12. The method of claim 9, wherein providing the notificationon the display comprises providing information about a location of theparticular component.
 13. The method of claim 9, wherein providing thenotification on the display comprises providing an instruction to removethe particular component from the mobile cleaning robot.
 14. The methodof claim 9, wherein the display comprises multiple regions, each regionrepresenting a respective component of the number of components of themobile cleaning robot.
 15. The method of claim 14, wherein providing thenotification comprises illuminating the region of the display thatrepresents the particular component.
 16. The method of claim 14, whereinthe multiple regions represent the drive wheel assembly, the cleaningassembly, a battery, and a cleaning bin, respectively.
 17. The method ofclaim 2, wherein providing the notification comprises providing anaudible notification.
 18. The method of claim 17, wherein providing theaudible notification comprises providing an audible instruction toremove the particular component from the mobile cleaning robot.
 19. Themethod of claim 2, wherein providing the notification comprises changinga color of an indicator.
 20. The method of claim 19, wherein providingthe notification comprises changing the color of the indicator toindicate a change in the operational status of the particular component.21. The method of claim 2, wherein determining that the operationalstatus of the particular component does not satisfy the conditioncomprises determining that an amount of charge or battery life in abattery of the mobile cleaning robot is below a threshold.
 22. Themethod of claim 2, wherein determining that the operational status ofthe particular component does not satisfy the condition comprisesdetermining that a fullness of a bin is above a threshold.